{"paper":{"title":"Space as a spectroscopic laboratory: High-resolution spectroscopy of the [$^{13}$C II] hyperfine structure with SOFIA/upGREAT","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Astronomical spectra from SOFIA yield the first experimental magnetic-dipole hyperfine constants for [13C II]","cross_cats":["physics.atom-ph"],"primary_cat":"astro-ph.GA","authors_text":"A. G. G. M. Tielens, C. Guevara, D. A. Riechers, J. Stutzki, L. Schneider, M. Mertens, N. Schneider, O. Asvany, R. G\\\"usten, R. Higgins, R. Simon, S. Kabanovic, S. Schlemmer, U. U. Graf, V. Ossenkopf-Okada, Y. Okada","submitted_at":"2026-05-08T16:50:34Z","abstract_excerpt":"The [$^{12}$C II] emission at 158 $\\mu$m is a key cooling line of the interstellar medium and traces gas kinematics in spectrally resolved observations. Its spectral profile is often modified by optical depth effects. The intrinsic line shape can be reconstructed by comparison with emission from the less abundant $^{13}$C isotope. Due to the additional neutron spin, [$^{13}$C II] emission splits into three hyperfine structure (hfs) transitions. Laboratory measurements have provided the centroid frequency and the strongest component ($F=2-1$); the two weaker components ($F=1-0$ and $F=1-1$) hav"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"From these astronomical data we determine, for the first time, the magnetic-dipole hfs constants A_{1/2}^{hf} = 810.71(11) MHz and A_{3/2}^{hf} = 162.18(5) MHz of the [^{13}C II] 2s^2 2p ^2P^o ground term.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The velocity distribution, excitation conditions, and line-of-sight structure are identical for the [12C II] and [13C II] emitting gas, so that the [12C II] profile can be used as an unshifted reference template for fitting the [13C II] hyperfine components without additional differential broadening or velocity offsets.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"SOFIA observations provide the first experimental magnetic-dipole hyperfine constants for [13C II] and refined centroid frequency using astronomical data.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Astronomical spectra from SOFIA yield the first experimental magnetic-dipole hyperfine constants for [13C II]","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"bec2235d5f3d38b84e09b7f998a1a666500b375e4b35f90b87aba8d7970189db"},"source":{"id":"2605.07995","kind":"arxiv","version":1},"verdict":{"id":"5dc57a7f-4779-41a9-82e8-ba754a2685b3","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-11T02:55:23.992083Z","strongest_claim":"From these astronomical data we determine, for the first time, the magnetic-dipole hfs constants A_{1/2}^{hf} = 810.71(11) MHz and A_{3/2}^{hf} = 162.18(5) MHz of the [^{13}C II] 2s^2 2p ^2P^o ground term.","one_line_summary":"SOFIA observations provide the first experimental magnetic-dipole hyperfine constants for [13C II] and refined centroid frequency using astronomical data.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The velocity distribution, excitation conditions, and line-of-sight structure are identical for the [12C II] and [13C II] emitting gas, so that the [12C II] profile can be used as an unshifted reference template for fitting the [13C II] hyperfine components without additional differential broadening or velocity offsets.","pith_extraction_headline":"Astronomical spectra from SOFIA yield the first experimental magnetic-dipole hyperfine constants for [13C II]"},"integrity":{"clean":false,"summary":{"advisory":0,"critical":1,"by_detector":{"doi_compliance":{"total":1,"advisory":0,"critical":1,"informational":0}},"informational":0},"endpoint":"/pith/2605.07995/integrity.json","findings":[{"note":"Identifier '10.1088/0004-637x/812/1/7510.48550/arxiv.1508.03801' is syntactically valid but the DOI registry (doi.org) returned 404, and Crossref / OpenAlex / internal corpus also have no record. The cited work could not be located through any authoritative source.","detector":"doi_compliance","severity":"critical","ref_index":59,"audited_at":"2026-05-19T11:20:47.213737Z","detected_doi":"10.1088/0004-637x/812/1/7510.48550/arxiv.1508.03801","finding_type":"unresolvable_identifier","verdict_class":"cross_source","detected_arxiv_id":null}],"available":true,"detectors_run":[{"name":"claim_evidence","ran_at":"2026-05-20T10:02:08.560369Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"ai_meta_artifact","ran_at":"2026-05-20T04:44:12.079785Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_title_agreement","ran_at":"2026-05-19T15:31:17.951292Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_compliance","ran_at":"2026-05-19T11:20:47.213737Z","status":"completed","version":"1.0.0","findings_count":1}],"snapshot_sha256":"01174444c29cb701d2d00b5d4cd26cd3c7f936d3c2069b97b34371cfb3ca9e5e"},"references":{"count":213,"sample":[{"doi":"10.1051/0004-6361/201935656","year":1904,"title":"A geometric distance measurement to the Galactic center black hole with 0.3\\. , keywords =. doi:10.1051/0004-6361/201935656 , archivePrefix =. 1904.05721 , primaryClass =","work_id":"44b94dff-a140-4f33-aee3-f6b4482af3e1","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1051/0004-6361/201014657","year":null,"title":"The physical properties of the dust in the RCW 120 H II region as seen by Herschel. , keywords =. doi:10.1051/0004-6361/201014657 , archivePrefix =. 1005.1565 , primaryClass =","work_id":"061850a8-5d93-418e-9d5f-989d88dbefc2","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1051/0004-6361/201117283","year":null,"title":"D., et al., 2012, @doi [ ] 10.1051/0004-6361/201117283 , https://ui.adsabs.harvard.edu/abs/2012A&A...542A..10A 542, A10","work_id":"66ad21a8-a646-41a6-b4f8-0d56ef61db9c","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1088/0067-0049/212/1/1","year":null,"title":"The WISE Catalog of Galactic H II Regions. , keywords =. doi:10.1088/0067-0049/212/1/1 , archivePrefix =. 1312.6202 , primaryClass =","work_id":"015b3dd5-c737-444e-9113-0bee41c673d5","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1088/0004-637x/800/2/101","year":null,"title":"Mopra CO Observations of the Bubble H II Region RCW 120. , keywords =. doi:10.1088/0004-637X/800/2/101 , archivePrefix =. 1412.6470 , primaryClass =","work_id":"f04ecae6-d196-41c5-847a-2d0e997bdc3b","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":213,"snapshot_sha256":"b955c71974914176eb110cd4a46328b5c1e51efa73596aec00d66e961738e9a6","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}